Press



April 30, 1940. F. LJOHNSON PRESS Filed Sept. 14, 1937 3 Sheets-Sheet lI INVENTOR FRANK L. J'oH/vs o/v ATTORNEY A ril 30, 1940. F. L-. JOHNSONPRESS Filed Sept. 14, 1937 3 Sheets-Sheet 2 INVENTbR FRANK L. JOHNSONATTORNEY Patented Apr. 30, 1940 a 7 UNITED STATES PATE oFFIcE 7 massFrank L. Johnson, Akron, Ohio Applioation septem ber 14,1937, SerialN0.163,790

15 Claims. (ems- 7) head, at .diametrically opposite points thereof. 2

This invention relates to presses, and more especially itrelates topresses of the general type commonly used in the rubber industry. forthe molding and vulcanizing of inner tubes and i pneumatic tirecasings.v I

The chief objects of the invention are to provide a press of simpleconstruction and economical operation; to provide'for the safety of theoperator; to provide rapidity of operation; to provide a press requiringrelatively smallfioor for cleaning and for mounting work therein andremoving it therefrom; and to provide a press design that is especiallyadapted for dual or tandem construction wherein two press units arearranged for concurrent operation by a power unit common to both ofthem. Other objects will be manifest as the specification proceeds.

Of the accompanying drawings: Figure 1 is a side elevation of the press,in its preferred form, in closed 'or operative position; Figure 2 'is asimilar View of the press, in its open or inoperative position;

Figure 3 is a section on the line 3-3 of Fig. 1; and

Figure 4 is a section on the line 4-4 of Fig. 1. Referring to thedrawings, I0 is a base casting and H, II are two vertical posts risingfrom the medial region thereof and supporting, a, plate or platform I2upon their upper ends. Journaled at itsrespective ends in the basecasting ill and platform 12 is a vertical feed screw l3 that is disposedbetween'the posts II and in the same plane as the latter, the lower endof'said feed screw extending below its bearing, within the base l0, andbeing provided thereat with -a gear l4. Meshed with the latter is apinion l5 that is mounted upon the lower end of a vertical drive shaftl6, which shaft is journaled in the base casting l0 and platform l2,parallel to driveshaft l6, and has driving connection at its upper endwith a reversible motor I! that is mounted upon platform I2. Thearrangement is such that motor I! drives the feed screw [3, but atreduced speed by reason of the speed. reduction between pinion l5 andgear M. The improved press preferably consists of two identical pressingunits, and is so illustrated in the drawings. Each of said pressingunits comprises an upper press head and a lowerjpress of arms or links24, 24 that have their upper ends .36 pivotally connected at125 to thesides-of the press pair of set screws: 28, 28.

space; to provide a press that is readilyaccessible "relation to saidlast mentioned portions.

arrangement is such that by angularly adjusting head 2|, which heads arehinged together in a manner presently to be described. Secured to the.

At their lower ends the links 24 are journaled upon a large hinge pin.21 adjacent the respective .endportions thereof, thelatter beingjournaled in the base casting I0, but normally being restraineda'gainstangular movement therein by a In like manner the upper press head 20 iscarried by a pair of arms or links 30, 30 that have their upper endspivotally connected to the oppositesides of the press head upon adiametric axis 3i. .At their lower ends the. links are journaleduponrespective end portions 32 of the hinge pin-21, which end portionsare disposed laterally outwardly of the portions on which the arms 24are journaled, and are eccentric with The the hinge pin 21 the links '30may be adjusted longitudinally relatively of the links 24 to the ,end.that the mold sections 22, 23 Ialways may be brought into pressingrelation to each other notwithstanding variation in the thickness ofdifferent mold sections that may be employed in the press. In theclosed,'oper'ative position of the press shown in Fig. 1, the links 24,30 of each press unit are substantially parallel to each other, with:the pivot points 25, 21, 3| and 32'substantially in alignment sothatmaximum pressure is exerted to close the mold sections upon the work.The'links 24, 30 are disposed at an angle to each other in the open,'inoperativeposition of the press, and this angular positioning is theresult of angular movement of the press heads .20, 2| upon their pivots3|, '25, respectively. The

aforesaid angular movement of. the press heads .is effected by movementof translation of the hinge. that connects the upper press, head 20 tothe lower press head 2 I, said movement of translation being in arectilinear course, and effected through the agency of the feedscrew l3.

To this end a nut 34 is threaded onto said feed screw, whichnut isformed with co-axial laterally projecting trunnions 35, 35 having atransversely disposed.- axis that is parallel to the hinge connecting:said press heads. Pivotally mounted upon said, trunnions arerespective, parallel,

equalizer members 36, 36, and carried by said members, in the oppositeends thereof, are hinge pins 31,31. vJournaled upon each hinge pin 31,between the members .36, is a guide shoe 38 that has a groove in one ofits faces for sliding engagement with the adjacent post H, said guideshoes thus preventing angular movement of thenut 34 and structurecarried thereby about the axis of feed screw l3. Each of the upper pressheads Zll is formed with a rearwardly extending bracket-arm 20a, andeach of; the lower press heads is formed with a similar bracket-arm 21a.

The arms 20a, 2 In of one press unit are pivotally pensate for anyslight mis-alignment of the press heads arising from unequaldistribution of the work in the molds or from other causes. To this endeach of the arms 20a, Zla is formed with an aperture or bore 40 that issubstantially larger in diameter than a hinge pin 31 and through whichthe latter extends. The outer end of each aperture .is counterbored, toreceive the frusto-conical head of a member 4| that is slidably mounteduponthe hinge pin, and is yieldingly urged toward thepress-head arm by acompression spring 42. The latter is mounted upon the hinge pinbetweensaid member 4| and a washer 43 that is retained on the end of the hingepin by a nut 44.

The reversible motor I! is provided with the usual switch means (notshown) for setting it in motion to open or close the press. It isdesirable, however, that the motor cease rotating automatically when thepress attains fully open or fully closed position, and to this endsuitable limit switches are provided. For supporting the limit switchesa vertical rod 45 having its end portions.

secured in the base plate I0 and platform l2 respectively is positionedat one side of feed screw it and parallel thereto. Upon the lowerportion of rod 46 is a slidably mounted switch support 4'! that may bekeyed thereon to prevent angular movement. The switch support ispositioned betwe'entwo collars 48, 48 that are adjustably secured totherod 45, and a compression spring as between the lower collar 48 and theswitch support normally urges the latter upward against the uppercollar. A limit switch 50 is secured to switch support 4! and projectsinto the path of a stud 5! that projects axially from. the adjacenttrunnion 35 of nut 34. In like manner the rod 46 carries an upper limitswitch 52 that is mounted upon a switch support 53 that is slidablymounted upon rod 46, near the upper end thereof, between collars 54, 54,there being a compression spring 55 between the switch support andtheupper collar. The limit switches 58, 52 are arranged in theelectrical circuit of the motor l'l'in such a manner as to open thecircuit and stop the motor when either switch is operated by the stud 5|as the latter reaches its lower or upper limit of travel. The presenceof the springs 49, 55 permits the motor I! to coast slightly after itscircuit is opened, without imposing undue strain upon stud 5| or eitherswitch mechanism.

As shown in Fig. 1, the molding cavity 26 in understood in the art.

The operation of the press is extremely simple. In the inoperative, openposition of the press shown in Fig; 2, the mold sections 22, 23 areextremely accessible for cleaning, and for the mounting of work in thelower mold sections. Observe the low elevation of the latter, and theabsence of obstructions in front of them, where the operator is requiredto work. As soon as articles to be pressed are mounted in the lower moldsections, the motor I1 is set in motion to drive the screw I3, wherebythe nut 34 is caused to rise and thereby to carry the pivot pins 37upwardly, with the result that the mold sections are brought into matingrelation and the links 24, 30 moved substantially into parallelism, asshown in Fig. 1, to produce a relatively high pressure upon the moldsections, yet requiring but a relatively small amount of power to do so.Furthermore, the same pressure will be exerted on the molds of 'bothpress units by reason of the equalizer members 36, which will tiltangularly upon the trunnions 35, if, through inequalities in the twounits, one becomes completely closed before the other. As previouslyexplainedfthe small amount of play in the hinge'connections between thepress heads also compensates for inequalities in the apparatus whichotherwise might impose severe strains upon the same. The upper limitswitch 52 is so positioned as to stop the opertion of the motor I! assoon as the mold sections are fully closed. The operations justdescribed are reversed to effect subsequent opening of the press. Thiscompletes a cycle of operation which is repeated as rapidly as theoperators can remove the finished work from the molds and recharge themwith work to be pressed. Although it is stated that the press heads 20,2| are hinged together 'by the respective hinge pins 37, this is nottrue in the sense that the press heads are supported by the hinges,since they are supported by the links 24, 30 and hinge about points 25,3| as axes. The pivot pins 3! are merely means, common to the two headsof each press unit, for the application of power to swing the said linksangularly and thereby to effect opening and closing of the press. Thefact that the power-driven nut 34 moves in a rectilinear course makes ita simple matter to position two press units back-to-back and operatethem concurrently by means of a single power unit, with resultingeconomies of power,

. space, and weight as previously explained. The

.dual arrangement of the presses enables the weight of either press tocounterbalance the weight of the otherpress so that lateral strain onthe feed screw I3 is avoided. The improved press provides safety andconvenience for the operator, and achieves the other objects set out inthe foregoing statement of objects.

Modification may be resorted to without departing from the spirit of theinvention, or the scope thereof as defined by the appended claims.

What is claimed is:

1. In a press, the combination of a base, .a pair of opposed pressheads, links supporting the respective press heads by means ofdiametrically disposed pivotal connections therewith, at one end of thelinks, the other ends of the links having pivotal support on the base,the pivotal supports for the links that support one mold section beingsubstantially co-axial with the pivotal supports of the links thatsupport the other mold section, and means connected to the press headsfor moving said links angularly of each other to effect opening and,closing or the press. i

2. In a press, the combination, of a 'base, a pair of opposed pressheads, links supporting the respective press heads by means ofdiametrically disposed pivotal connections therewith, at one said pivotpin, a press head pivotally supported by the other ends of said links, apair of links journaled at one end on the concentric portion of saidpivot pin, a second press head opposed to the first mentioned press headand carried by the other ends of the last mentioned links, and meansconnected to said press heads for moving said links angularly relativelyof each other to open and close the press.

4. In a press, the combination of a base, a pair of opposed press headshaving pivotal connection with each other, links supporting therespective press heads by means of diametrically disposed pivotalconnections therewith, at one end of the links, a pivot pin in said baseupon which pin the other ends of the links are pivotally mounted, andpower means having operative connection with the pivotal connectionbetween-the press heads for swinging the links angularly relatively ofeach other to open and close the press.

5'. A pivotal connection between the heads of a press that comprises apair of opposed press heads, and respective pivotal supports for saidheads enabling them to swing angularly in the opening and closing of thepress, said pivotal connection between the heads being so constructedand arranged as to provide play thereat,

yielding means resisting said play, a power memher, and means forapplying the power thereof to the said pivotal connection to effectopening and closing of the press.

6. A pivotal connection'between the heads of a press that comprises apair of opposed press heads, and respective pivotal supports for saidheads enabling them to swing angularly in the opening and closing of thepress, said pivotal connection comprising a hinge pin having appreciableplay between it and the heads, yielding means normally resisting saidplay, and power means connected to said hinge pin for moving the.

latter in a direction that swings the press heads angularly on theirsupports.

'7. A pivotal connection between the heads of a press that comprises apair/of opposed press heads, and respective pivotal supports for saidheads enabling them to swing angularly in the opening and closing of thepress, said pivotal connection comprising a hinge pin that extendsthrough apertures of larger diameter formed in projecting portions ofthe respective press heads, said apertures being countersunk at one end,complementally shaped members mounted upon the hinge pin and seated inthe respective countersinks, compression springs backing said membersand urging them into said countersinks so as normally to maintain thehinge pin in concentric relation tosaid apertures, and

power means connected to said hinge pin .for'

moving the latter in a direction that swings the press heads to open andclose the press.

8. In a press, the combination of a pair of opposed press heads,respective pivotal supports for said heads enabling them to swingangularly in the opening and closing of the press, a pivotal connectionbetween said heads, and means for moving said pivotal connectionbetween'the press heads in a rectilinear course to effect opening andclosing of the press.

9. In a press, the combination of a pair of opposed press heads,respective links upon the free ends of which said press heads aremounted,

a pivot pin common to said links upon which their other ends arepivotally mounted, a pivotal connection between said press heads, andmeans for moving the last mentioned pivotal connection in a rectilinearcourse to effect opening and closing of the press.

10. A combination as defined in claim. 9 in which the pivot pin commonto the links is so positioned with relation to the press heads that thelinks are substantially in alignment in the closed position of thepress. v

1 1. In a press, the combination of a pair of adjacent press units, eachof said press units comprising a pair of tiltable press heads havingpivotal connection with each other, said pivotal connections beingdisposed adjacent each other, and a power-driven member movable in arectilinear course and having operative connection with both of saidpivotal connections for effecting concurrent operation of both pressunits.

12. In a press, the combination of a pair of press units disposed backto back, each of said units comprising a pair of tiltable press headshaving pivotal connection with each other, said pivotal connectionsbeing disposed adjacent each other, a power driven member moving in arectilinear course, and equalizer means operatively interposed betweensaid power driven member and both of said pivotal connections, wherebyequal power is delivered-to each of the latter to effect opening andclosing of both press units.

13. In a press, the combination of a pair of press units disposed backto back, each of said units comprising a pair of tiltable press headshaving pivotal connection with each other, said pivotal connectionsbeing disposed adjacent each other, a power driven member moving in arectilinear course, and equalizer means comprising a member that ispivotally connected at its middle to saidpower driven member andconnected at its respective ends to. the respective pivotal connectionsbetween said press heads.

14. In a\ press, the combination of a pair of press units disposed backto back, each of said units comprising a pair of tiltable press headshaving pivotal connection with each other, said pivotal connectionsbeing disposed adjacent each other, a feed screw positioned,intermediatesaid pivotal connections, a nut on said feed screw, a pair of parallelequalizer elements swiveled at their medial region on said nut andhaving their ends connected to respective pivotal connections

